Through the clear blue water, you can see beautiful white sand on the ocean floor. The beaches are crowded with young people enjoying diving and families.
This is Zamami Island in Zamami, Okinawa Prefecture, to the west of Okinawa Island.
Near the end of World War II, US forces landed on the Kerama Islands, including this island, on March 26 and 27, 1945, sparking the Battle of Okinawa (See below).
The Japanese military repeatedly told the islanders that if they fell into the clutches of American soldiers, women would be raped and men would be killed, a prospect that drove many to commit group suicide.
Across the islands, more than 600 people perished through suicide. Zamami Island saw 234 residents kill themselves - the second-largest number after 330 deaths on Tokashiki Island, also one of the Kerama Islands.
"The sea was filled with US ships," said Fumiko Miyamura, 89, furrowing her brow at her home near Zamami Bay of the island. "There were so many, it looked as if you could walk on them to get to the next island."
Miyamura was 19 at the time. She saw lines of US soldiers coming to her village after landing. She fled to a nearby cave to hide, where she found dozens of bodies of women and children.
She realised instantly that her uncle, who was still in the cave, had killed his wife, children and grandchilden with his own hands.
"Do you want to die, too?" he asked with a blank expression on his face.
"Absolutely not," she said.
The uncle then hanged himself after saying, "My children are waiting for me."
Mie Tanaka, now 84, was 14 at the time. She escaped to a different cave with her friends and a homeroom teacher.
"Let's kill ourselves," the teacher said and pulled the pin of a hand grenade he was holding. However, it failed to explode. Tanaka fled the cave, frightened.
Tanaka told us the way to that cave, which is located on the shore of the north side of the island. At high tide, the cave cannot be approached from land.
Feeling the spray of the ocean, about 100 people were packed into the cave of about 10 meters square at that time, according to Tanaka.
Frightened, they must have sat huddled together. The sound of the wind echoed throughout the cave, and it was like the wails of those islanders caught in a choice between life and death.
The Tower of Peace stands along the side of Mt. Takatsuki, 131 meters above sea level. It takes about 10 minutes to walk there from Zamami Bay. The tower is dedicated to those killed in the battle.
Facing away from the tower, you can see the bay, the Zamami village, and in the distance, Aka Island, which is also part of the village.
It is said that a unit of the Japanese military on Aka Island did not believe the war had ended and kept fighting for seven days after Aug. 15, 1945.
After 70 years, there are fewer and fewer people who remember such stories. Most of the 200,000 people visiting the island annually are tourists.
After the war, many residents on the island opened inns for such tourists. Tanaka is among them.
"I had terrible, terrible experiences," she said. "Since our island is filled with smiles today, I don't ever want to have the same experience again, nor do I want any children to experience it."
She then looked at the parents and children playing in her inn's dining room.
Preserving local scenery
The Kerama Islands are made up of about 30 large and small islands, including Zamami, Akashima and Tokashiki islands. They were originally called "Kirama."
In the 1200s, the islands became important stops for trading ships traveling between Okinawa Island and China. In the early 1900s, bonito fishing made the islands prosperous.
However, the islands were radically changed during World War II. US bombardment by sea and air destroyed houses and turned the islands into completely burned-out ruins. The residents faced difficult times thereafter, but the islands have recovered with tourism as their main industry and now have about 1,500 residents.
The waters here are said to be some of the clearest in the world, and their colour is called "Kerama Blue." About 250 varieties of coral grow in the waters around the islands.
You can enjoy diving year-round, and whale-watching is popular in winter as you can watch humpback whales at close range.
The beautiful scenery and the biodiversity of the Kerama Islands are highly evaluated. Last March, the islands and their surrounding waters were designated as Japan's 31st national park.
There have been threats to the local environment, however. In 1998, rising water temperatures and other factors caused the bleaching and dying out of parts of the coral population.
From 2001 to 2006, large numbers of crown-of-thorns starfish, which prey on coral, appeared. Local divers and fishermen battled the creatures every day.
The villages of Zamami and Tokashiki have established a local council to promote ecotourism. They are trying to preserve the beautiful natural environment by limiting diving spots, among many other efforts.
■ The Battle of Okinawa
The Battle of Okinawa was the second battle to occur on land in Japan during the Pacific War, following on the heels of the Battle of Iwo Jima on a remote island that is officially part of Tokyo.
After taking the Kerama Islands, US forces reached Okinawa Island on April 1, 1945. The fierce bombardment from the sea, which was later called the "Typhoon of Steel," sent the Japanese soldiers and civilians fleeing in panic. On July 23 of the same year, Mitsuru Ushijima, commanding general of the Japanese troops on the island, committed suicide in the underground headquarters beneath the southern part of Okinawa, ending the organised battle.
Including residents, there were over 190,000 casualties on the Japanese side. The US forces suffered 12,000 casualties.